Chapter 4. Operation
36 | ADTS 405 R/F Mk2 Instruction Manual-English
© 2017 General Electric Company – All Rights Reserved.
the range of the pitot channel, i.e. either 850 or 1,000 kts. See
4.7 Changing Parameters
4.7.1 Mach Test and Constant Mach
To go to 0.8 Mach, enter Control Mode and proceed as follows:
a.
Press
SPEED
then
RATE
to select rate of change of airspeed.
b.
Enter required rate, e.g. 300 kts/min.
c.
Press MACH.
d.
Enter 0.8.
e.
Wait for the Mach to be achieved.
Note:
If the altitude changes the system automatically adjusts the airspeed to keep the
Mach value constant.
4.7.2 True Airspeed
The normal airspeed parameter is Calibrated Airspeed (CAS) (equivalent to IAS for testing
purposes).
The airspeed parameter may be changed to True Airspeed (TAS) as follows:
a.
Press
SETUP
then
SPEED
.
b.
Select [CAS/TAS].
c.
Select [TAS].
d.
Press
QUIT/CLEAR
repeatedly to exit setup.
e.
Press
SPEED
.
The display now shows the airspeed parameter as TAS.
Note:
Airspeed parameter type can only be changed in Full Setup mode. Rate of change
of airspeed will still be shown as Rate CAS.
Pitot temperature (
θ
t) is used in the calculation of TAS. Pitot temperature can only be
changed in Full Setup mode. To enter (
θ
t):
a.
Press
SETUP
.
b.
Press
SPEED
.
c.
Select [Pt TEMPERATURE].
d.
Enter the temperature measured by the aircraft's pitot temperature sensor.
e.
Press
QUIT/CLEAR
three times to return to user display.
4.8 Airspeed Switch Test
The following example shows how an airspeed switch can be functionally checked.
Note:
For low airspeed switches (i.e. 130 kts) the Pt Only facility could be used.